1. Field of the Invention
This invention relates to a power-circuit breaking device (service plug) for breaking a current flow by opening a power circuit.
2. Description of the Related Art
Because capacity of a power source such as a battery in an electric vehicle is greater than that in a normal vehicle with a gasoline engine, it is required for safety in working to open the power circuit by using a power-circuit breaking device (service plug) when maintaining an electric system. Such power-circuit breaking device in the prior art is generally presented by a power-circuit breaking device 101 shown in FIGS. 7, 8 (Refer Patent Document 1: Japan Patent Published Application No. H10-83753).
The power-circuit breaking device 101, as shown in FIG. 7, includes a first connector housing 102 having a pair of female terminals 120 connected to a terminal portion of an open power circuit and a second connector housing 103 for electrically connecting the pair of female terminals 120 to each other. The second connector housing 103 includes a pair of male terminals 130 connected with the pair of female terminals 120, a fuse 140 arranged between the pair of male terminals 130 and a housing 144 receiving the pair of male terminals 130 and the fuse 140.
The fuse 140 includes a fuse element received in a plastic fuse body 141 and a pair of metallic tabs 142 having one end portion thereof connected to the fuse element and the other end portion thereof projecting outwardly from the fuse body 141. As shown in FIG. 8, the pair of male terminals 130 is inserted through holes provided at the other end portions of the metallic tabs 142, and screwed with nuts 143 so that the fuse 140 is jointed integrally with the pair of male terminals 130.
According to such power-circuit breaking device 101, the first connector housing 102 and the second connector housing 103 are connected to each other so that the female terminals 120 and the male terminals 130 are fitted together so as to close the power circuit. Inversely, by releasing fitted terminals, the power circuit is opened. When an overcurrent flows through the close power circuit, the fuse element of the fuse 140 would be blown out so as to open the power circuit and break the current flow.